This post will help you find the switch OS user manual and release notes.
1. On Mellanox.com, see
2. In case you have a Mellanox switch you can simply do the following:
2.1. login to the switch webGUI, and click on top right side the Product Documentation
2.2 Click on the User Manual Tab to open the User Manual.
3. In case you have support account, you can login to myMellanox site and download all manuals there.
Browse to the required product (e.g. SX1710), click on Documentation, and filter the latest version.